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Open WellbeingWhat the studies actually measured

Cholesterol and blood fats

Niacin (vitamin B3)and HDL cholesterol

Both sources here measured higher HDL cholesterol.

How sure anyone can be

Moderate certainty, level 3 of 4

Further research may change this.

The most certain of the two findings here; each record carries its own.

The numbers reported

One source’s range, drawn against its own line of no difference and scaled to its own numbers.

0.240.27 mmol/L0.3

This range stays on one side of the no-difference line.

Bar the confidence interval — the range the true effect is likely to sit inNotch the number the source reportedLine where there would be no difference at all

Two sources, newest first

What we read is the published abstract, not the full paper, so a blank below may still be printed in the paper itself. A fixed rule worked this out from the source’s own fields. Nobody checked this rating by hand.

  • Systematic review, 2015

    Moderate certainty, level 3 of 4

    Effect of niacin on lipids and glucose in patients with type 2 diabetes: A meta-analysis of randomized, controlled clinical trials.

    Clin Nutr. 2015;34(5):838-44. doi:10.1016/j.clnu.2014.09.019. PMID:25306426.

    Number reported
    0.27 mmol/L
    Which way it went
    Higher
    Likely range
    0.24 to 0.3
    Source’s own words
    mmol/L HDL cholesterol weighted mean difference vs control
    Who was studied
    Adult with type 2 diabetes
    Compared with
    control
    Amount taken
    Not in the abstract
    For how long
    Not in the abstract
    Disagreement between studies
    significant heterogeneity reported for LDL-c and fasting glucose, not for HDL-c
    Kind of record
    Journal article
    How this rating was reachedstarts at High, one step down: imprecision
    1. Starts at High
    2. Imprecision brought it down to Moderatethe abstract does not state how many participants were pooledNot in the abstract
    3. Ends at ModerateOne step down.
    Checked, nothing to step it down for
    risk of bias and indirectness
    Inconsistency
    No disagreement reported, and no count of studies behind it

    Imprecision stops at the first check that applies; others may apply too.

    AI review could not confirm it — an AI agent re-read this finding against the saved source and at least one check failed. The batch record names the check and quotes the sentence that caused the doubt. No person read it.

    Read the abstract on PubMed

  • Systematic review, 2005

    Low certainty, level 2 of 4

    Efficacy and safety of high-density lipoprotein cholesterol-increasing compounds: a meta-analysis of randomized controlled trials.

    J Am Coll Cardiol. 2005;45(2):185-97. doi:10.1016/j.jacc.2004.10.031. PMID:15653014.

    Number reported
    16 percent change
    Which way it went
    Higher
    Likely range
    Not in the abstract
    Source’s own words
    % relative increase in HDL-C with niacin (fibrates 10% in the same analysis)
    Who was studied
    Adult
    Compared with
    trial control arms
    Amount taken
    Not in the abstract
    For how long
    Not in the abstract
    Disagreement between studies
    random-effects model; no I2 or CI given for the lipid percentages
    Kind of record
    Journal article
    How this rating was reachedstarts at High, 2 steps down: risk of bias and imprecision
    1. Starts at High
    2. Risk of bias brought it down to Moderatethe abstract reports no risk-of-bias or quality appraisal, so study limitations cannot be ruled outNot in the abstract
    3. Imprecision brought it down to Lowthe abstract reports no confidence interval for the estimateNot in the abstract
    4. Ends at Low2 steps down.
    Checked, nothing to step it down for
    indirectness
    Inconsistency
    No disagreement reported, and no count of studies behind it

    Imprecision stops at the first check that applies; others may apply too.

    AI-reviewed & signed — an AI agent re-read this finding against the saved source and checked that the quote, the numbers, the units and the direction match it. No person read it. The owner authorised the agent to sign the batch with the owner's key, and every build rechecks that signature against these exact bytes.

    Read the abstract on PubMed

What is still missing from these readings

  • One gives no likely range, so how precise that number is is unknown.
  • Two do not say how many people took part.
  • Amount taken — Not in the abstract.
  • For how long — Not in the abstract.

Something nobody wrote down is never a zero and never a guess.

Nothing left on our list for Niacin (vitamin B3)

All four things on our list for Niacin (vitamin B3) have been read. That is rare here.

Still to read means nobody here has got to it, not that it was tried and did nothing or that no research exists. A pairing on no list is not a gap: we never set out to read it.

Read next

This is a library, not advice. No recommendation, no dose, no diagnosis, no ranking. We never ask about your symptoms, and nothing here is tailored to you.